Automatic door-closer



HQ L. CLAESSON. AUTOMATIC DOOR CLOSER. APPLICATION FILED vac-22. I916.

Patented July 13, 1920.

H L CIaawon l m/(Zn r HELG-E LINUS GLAESSON, OF GOTTENBOBG, SWEDEN.

AUTOMATIC DOOR-CLOSER.

Specification of Letters Patent.

Patented July 13, 1920.

Application filed December 22, 1916. Serial No. 138,364.

This invention refers to automatic door closers of the type wherein a positively actuated member such as a spindle operated by a torsion spring acts on the door as well as on the door post in such a way, that the tension of the spring by the revolving of the spindle is increased, when the door is opened, and by the influence of this increased tension actuates the door so as to close the same.

The object of the present invention is to provide certain improvements in the construction, arrangement and operation of automatic door closers of the type above mentioned.

In accordance with one of the important features of this invention an apertured piston is movable axially within the casing of the door closer but is prevented from rotat1on in said casing and a threaded member within the casing co-acts wlth said piston,

u the memberand casing being relatively rotatable to effect axial movement of the piston, and valve means being provided on the threaded member operatlng in one direction of movement thereof to open the.

aperture in the piston and in the other direction of movement of the member to close said aperture. 1

According to another important feature of the invention, the casing of the door closer is provided with a bore at one end thereof and a shaft is mounted in the casing bearing in said bore, and means are provided for yieldingly resisting relative movement between said casing and shaft in one direction and to effect relative movement therebetween in the reverse direction, a screw coaxial with said shaft, having a piston and a check valve internally threaded and mounted nut-like on .said screw, with means limiting said piston to axial motion. 7 i v The invention also comprisesthe particular constructions and arrangements of parts hereinafter more fully described and clearly pointed out in the appended claims.

The improved device can be applied to almost any type of automatic doorcloser, and I do not want to limit myself to any special type of such apparatus, but to facilitate the understanding of the improvement and how it is to be applied and worked, I will here explain the same as combined with a special embodiment of automatic door closer.

In the accompanying drawing Figure 1 is a sectional elevation through the automatic door closer proper of the embodiment here chosen as an example, Fig. 2 is a plan view of a door provided with the improved door closer in the shut position, Fig. 3 is a similar view with the door opened up and, left to itself, being closed in the automatic manner by the apparatus. Fig. l is a" similar view but illustrating how the door is closed by the influence of an excessive positive force. Fig. 5 is a cross sectional view showing the connection between the piston and the threaded member and casing.

The device illustrated comprises a cylindrical casing 1 closed at the bottom and having a bore through its top. lVithin the cylinder is a piston a restricted to axial motion by a vertical guide 5 secured to the inner wall of the cylinder and fitting into a corresponding groove in the piston wall. The piston is provided, see Fig. 5, with a central substantially oblong bore 6 through which the spiral or screw 7 passes. The piston l at opposite sides of'the bore 6 is formed with clearance spaces 6 sufficient to permit the free flow of fluid therethrough. The spindle 8, to which the screw is rigidly connected, fits into a bearing in the bore at the top of the casing, the hub 9 of the spindle extending beyond the top.

The bore 6 on the rear side relatively to the spindle 8 is closed by a check valve 10 frictionally mounted on the worm '7 the movement of which valve is limited by stops or projections 19.. The check valve 12 is internally apertured so as to fit closely about the screw 7; this close fit prevents any flow of fluid between the screw and the valve. The spindle 8 is actuated by a helical spring 13 the one end of which is secured to the spindle, in any suitable manner as at a while the otherend of the spring is secured to the case '1 so that, when ,revolving the spindle, the tension of the spring is increased and" the spring thus acts to return, the'spindle 8 intoits original position. r

The case 1 will be mounted on the door post 17 by means of screws through apertures 2 in a lug 3 projecting from the case 1.:

may in reality with the same result be inter changedz'. e. the case 1 may be applied on the door and the member 15 connected with the door post.

The working of the apparatus may be clearly understood from what is mentioned above in connection with the following description. In shut position the member 15 is stretched and keeps the door closed (Fig. 2). WVhen the door is opened the member 15 transmits the motion to the arm 14: and turns the spindle 8 with the screw 'member' or worm 7 whereby the piston 1 is caused to move upward (in respect to the position illustrated in Fig. 1) and at the same time the spring 18 istensioned. The check valve 10, because of its adhesion'to the screw rotates with the latter without axial motion until the piston 4 has advanced a distance in combination a casing, an apertured piston sufficient 'to bring the projections 12 into contact with the valve, after which the piston carries the valve upward, The checking means consists of a fluid in the casing 011 both sides of the piston 4:, which fluid during the upwardmotion of the piston has a free passage through the bore '6 to the underside of the piston, so that it does not prevent the even upward'motion of the piston. thedoor is left to itself, the tensioned spring 13 tends to revolve the spindle 8 in the opposite direction whereby the screw 7 causes the piston et-to descend. Asthe piston descends the valve 10 turns with the screw until the under surface of the pistonmeets the ;valve, after which they bothdescend to gether. The. fluid is thus prevented from freely passing through the bore 6 by the valve 10. However, the piston is not fully fluid tight around its circumference and thus the fluid is allowedto escape,though with a rather slow flow-e-from the lower. side of the piston to the upper side, so that the piston is allowed todescend slowly, and checks in this way the revolving motion 'ofthe spindle Send the closing speed of the door, which. consequently reaches the shut position with an even motion without shock against the door post (Fig. 3).

Any positive closing power set up on the door, however, causes the flexible member 15 to yield as shown in Fig. 4 and the door can If now 7 be shut more quickly than in fact allowed by the checked apparatus proper, and the latter will not be damaged.

Having thus described my said invention and how it is to be performed, what I claim as new and Want to protect by Letters Patent is:

1. In a device of the character described, in combination a casing, an apertur ed piston movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said member and casing being relatively rotatable to effect axial movement of said piston, and valve means on said threaded member operating in one direction of movement thereof to open the aperture in the piston, and in the other direction of movement thereof to close said aperture.

2. In a device of the character described, in combination a casing, an apertured piston movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said member and casing being relatively rotatable to eifect axial movement of said piston, and valve means frictionally mounted on said threaded member operating in one. direction of movement thereof to open the aperture in the piston, and .in the other direction of movement thereof to close said aperture.

3; In a device of the character described,

movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said memberand casing being relatively rotatable to eifect axial movement of said piston, a helical spring operatively connected to said casing and threaded member and tensioned by relative movement between said casing and member in one direction to eifect relative movement thereof in the reverse direction, and valve means carried bythe threaded member for controlling the aperture in the piston. A

4. In combination with a fixed support and a door hinged thereto, a casing fixed to i said support, an exterior operating arm exmember yieldable' transversely of its length secured at one end to said arm and at the other end to said door, an apertured piston movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said member being rotatable by saidrarmto efi'ect axial movement of said piston, andvalve means on said threaded member operating in one direction of move ment thereof to open the aperture in said piston, and in the other direction of move ment thereof to close said aperture.

5. In a device of the class described, in

combination a casing, an apertured piston movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said-member and piston being relatively rotatable to eiiect axial movement of said piston, a helical spring operatively connected to said casing and threaded member and tensioned by relative movement be tween said casing and member in one direction to effect relative movement thereof in the reverse direction, and valve means on said threaded member operating in one direction of movement thereof to open the aperture in said piston, and in the other direction of movement thereof to close said aperture.

6. In combination with a fixed support and a door hinged thereto, a casing fixed to said support, an exterior operating arm extending from said casing, a flat resilient member yieldable transversely of its length secured at one end to said arm and at the other end to said door, an apertured piston movable axially within said casing but prevented from rotation therein, a threaded member within said casing co-acting with said piston, said member being rotatable by said arm to effect axial movement of said piston, a helical spring operatively con nected to said casing and threaded member and tensioned by relative movement between said casing and member in one direction to effect relative movement thereof in the reverse direction, and valve means on said threaded member operating in one direction of movement thereof to open the aperture in said piston, and in the other direction of movement thereof to close said aperture.

7. A device of the character described comprising casing having a bore through one end, a spindle mounted therein bearingin said bore, a screw coaxial with said spindle, an apertured piston arranged about and movable by the screw, a check valve mounted on the screw in such manner as to close the aperture, and means on the valve for limiting said piston to axial motion.

8. A device or the class described, comprising a casing having a spindle mounted therein, a screw co-axial with said spindle, a helical spring surrounding said spindle having one end fixed to said casing and the other end fixed to said spindle, an apertured piston mounted nut-like on said screw, and

a check valve similarly mounted on said screw and movable thereby to alternately open and close said aperture in said piston.

9. A device or the class described, comprising a casing, a spindle mounted therein, means yieldingly resisting relative movement between said casing and screw in one direction and operative to cited: relative movement therebetween in the reverse direction, a screw co-axial with said spindle, a piston threaded on said screw to provide a clearance space for the flow of fluid therethrough, a check valve frictionally mounted on said screw to prevent the flow'of fluid between said valve and said screw, said valve being movable by rotation of the screw relatively to the casing to open or close said clearance space, and means on said piston to limit said movement of said valve.

10. A device of the class described, comprising a casing secured to a door support, having a spindle mounted therein projecting through the top of said casing, a screw coaxial with said spindle, a helical spring surrounding said spindle having one end fixed to said casing and the other end fixed to said spindle, a piston mounted nut-like on said screw, a check valve similarly mounted next the said piston, an operating arm rigidly connected to said exterior portion of said spindle, and a soft plate spring linked between the free end of said arm and the door.

11. A device of the class described comprising a casing, an apertured piston within said casing, a screw within said casing having screw-threaded connection with said piston, said screw and said casing being relatively rotatable to effect axial movement of said piston, means yieldingly resisting relative movement between said casing and screw in one direction and operative to eitect relative movement therebetween in the reverse direction, valve means co-acting with the piston aperture having threaded connection with said screw and movable thereby axially to alternately open and close the piston aperture, and means on said piston to limit the axial movement of the valve means in both directions.

In testimony whereof I affix my signature in presence of two witnesses.

HELGE LINUS OLAESSON.

l Vitnesses GUsTAF Gnnr, ALEX FAYELBENG. 

